When do yous believe bitcoin will become a mainstream currency accepted for over 70% of services and goods in any country worldwide?

As time goes by this is becoming more possible and if it going to happen it will more than likely be the next five years. Your vote and comments are welcomed.

2017+

It's more likely that informal networks will develop. For example in Argentina. Their money is being inflated away, with inflation at around 25%. To protect their wealth, they've started to buy high-end cars (such as BMWs). But how many cars can one person buy?

My guess would be 2020 or later if I had to pick an exact date. But this is sheer speculation to me. Right now, bitcoin is kind of like the internet was in 1991 - it exists, but it's a novelty to most people. There are still a lot of people out there who haven't even heard of it.

In my opinion, the single best thing that could happen to bitcoin would be if a major online retailer started accepting bitcoins for payments. People talk about WordPress like it's a big deal, but really most non-geeks or webmasters don't know or care about WordPress. I'm talking on the scale of eBay or Amazon.

To me, Amazon is the benchmark, the day they start accepting bitcoin for payments is the day that it's truly gone mainstream. However, as much as I'd love for that to happen, I'd rather it happen later than sooner. The bitcoin economy simply isn't ready for that big a retailer to start accepting bitcoin yet.